The majority of the noise will be coming from I5. This is a very common question that my clients ask and I always suggest that they visit the location especially during the high traffic times. Other factors with in the property and the buyer play a large roll in the noise as well. For example if the home's backyard is on the side of the home that is not facing the Highway it may dampen the over all noise, which could be something the buyer is okay with or it does not bother them. It is a personal preference as to what you are okay with.
If there are ever any homes in the area that you would like to see please let me know and I would love to set up a showing. : )